Piston



Dec'. v29 1925. 1,567,398

' W. J. SIX

Filed June 20l 1925 P' lq. 1 /f ,l '-12113 p INVENTOR. l Wurf/e J'. 5m.

ATTORNEYS.

' .ramas me 29, 1925.

` 'WALTER if. sur, or INDIANAPOLIS, INDIANA.

PISTOIT.

Application flied June 2 9, 1925. Serial No. 35,517.

'ilk/'till whom it may concern:

@Beit known that I, WALTER J. Six, a citi- 'ien of the United States, and a resident of indianapolis,'county of Marion, and State of Indiana, have invented a certain new and useful Piston; and I do hereby declare that i 'the following is a full, clear, and exact description thereof, reference `being had to the "accompan .ing drawings, in which rlike numerals re er to like parts.

This invention pertains to pistons particularly adapted for use in internal combusl tion engines. i

' ,f The object of theinvention is to provide a piston ofthe usual character but differing from pistons of ordinary structure in that theskirt portion thereof is formed sepa- 'ately from the head and rigidly secured rheretoso that it may be made from sheet metal provided with separate and spaced bearing faces. T he sheet' metal is such th`at the bearing faces may engage the' cylinder wall under spring tension so as to conform thereto and eliminate sla of the piston while at the same time avoiding any'danger of seizing and scoring. This'piston structure yenables istons to be installed in reground cylin ers as well as others Without the necessity of obtaining an exact fit.

The full nature of the` invention will be understood from the accompanying drawings and the following description and claims:

Fig..l is a centralvertical section through l5 -a portion of the cylinder wall showing the piston mounted therein in elevation. Fig. 2 is the seme as Fig. 1 showing the bearing .side of the"piston. Fig. 3 is a central vertical section-down through the bearing sur- W faces of the skirt of. the piston showing the same in expanded position.V Fig. 4 is a lan view looking at the top of the piston rom -the under side thereof, when in expanded position.

In ,the drawings there is shown a cylinder 10 in which the piston is mounted so as to reciprocate therein in the usual manner. .'-lhe piston shown herein comprises a cast metal head 11, having the usual iianged periphery i2 provided with a plurality ot' peripheral grooves 13 adapted to receive the usual.- piston rings 14. Cast integral with the head, are the wrist pin bosses l5, extending downwardly from the opposite sides of .5 5 the head 4or-the flange portion i2 thereof,

tension. Thus,

and connected thereto by the web portion l Whereas, heretofore, it has been the custom to cast the head, skirt and wrist pin bosses integral, in this instance, only the head with its depending ange and the wrist pin bosses are cast in one piece, and the skirt is formed separately therefrom ot' sheet metal, after which it is rigidly secured to the head as will be described.

The skirt is herein shown as a sheet metal stamping wherein there isformed the oppositely disposed bearing portions i7 spaced from each other, said bearing surfaces couforming substantially to the curvature of the head. Toward the top thereof, thc metal is reduced or cut away'to provide thc oppositely disposed reduced neck portions 18, Said reduced neck portions terminate in a connecting strip 19 between the bearing portions 17, so bent as to extend upwardly within the fiange portion of the head and fit snugly against the under surface of the head, between the Wrist pin bosses as shown in Fig. 3. This connecting strip 19 is rigidly secured to the under surface of the head by the bolts 20, or it may he rigidly welded or secured thereto by any other suitable means.

The sheet metal, of which the skirt is formed, has a certain springlike characteristic, such that the skirt portions 17 may hc compressed toward each other under spring before the .piston is installed,` the skirt portions 17 are flared outwardly or expanded to a slight degree' as shown in Fig. 3. Upon insertion in tinl cylinder, they will be compressed toward cach other and bear against the wall of the cylinder under spring tension as shown in Fig. 1. By reason of the reduced neck port-ion 1S, as well as the free portion of the connecting hand 19, the spring movement will he taken up at a point adjacent the head. As the skirt may readily be compressed, there can he no seizing or scoring of the piston or cylinder, and as there is a constant outward )ressurcexerted by the skirt against the wail of the cylinder, a close fit will be assured, thus preventing any slapping. The heat acquired by the piston and particularly the head thereof can have no material effect. upon the expansion or contracting ot' the skirt for the above reasons, Thus, the expansion and contraction of the metal used is of no consequence.

suitable metal such ,as bronze,

The skirt portion may be formed of any alnminum or any metallic com ositions,zan`ibyf reason of its character, an thel large ofthe skirt which is cut away, th piston will be relatively li ht as compared with other structures. urthermore it is adaptable to accommodate itself to slightlyvarying sizes of cylinders, thus enabllng its installation to be simplified as well as permitting its ready adaptability to reground cylinders. Thus, the characteristics of this piston have many advantages which may .readily occur to those familiar with the art.

The invention claimed isz.

1. A piston comprising a cast metal head provided with double wristpin bosses cast. the under top surface there-- of, and a skirt formed of sheet metal sepaintegral with rately from said head, said skirt being rigidly secured to the under top surface of said head intermediate said bosses.

2. A piston comprising a cast metal head provided with depending wrist pin bosses castv integral with the under top surface thereof, and a Skirt formed of sheet metal separately from said head, having oppositely lformed with downwardly disposed bearing ,surfaces spaced fromeach other, said skirt beingl secured to the under top surface Qof said head intermediate said bosses.

3.' A piston having downwardly extendin integral therewith, an a skirt formed from sheet metal independently of said head having o positely disposed bearing surfaces separat and space from each other, a connecting band between the bearin surfaces of said skirt and means for rigi 1y securing said skirt to the under side of said head.

a cast metal head, wrist pin bosses cast 4. A piston comprising acast metal head extendin wrist .pin bosses cast integral withsaid ead, a skirt-of sheet metal, formed separately from said head, and having oppositely disposed bearing surfaces separated and spaced from each other, and a connecting strip connecting the upper portions of said bearing surfaces with each other and rigidly secured to the under side of said head intermediate the bosses. y

In witness whereof,I have hereunto affixed my signature.

- WALTER J. SIX.: 

